Optical triangulation is commonly used to determine the position in space of a point on an object. One type of optical triangulation system commonly utilizes two-lens systems: a projection lens system to project a light beam to the object and a receiving lens system to receive reflected light. Information derived from the position of the received light is used to determine the position of the object.
Other types of optical systems project light to the object and determine the position of the object by sensing the degree of focus of reflected light after being processed by a lens system.
In general, these two types of optical projection systems are complex. Further, when these systems utilize laser light, the systems are subject to the influence of a characteristic inherent in many laser light sources, namely, pointing instability. Pointing instability refers to the sporadic and unpredictable angular deviation of the laser light beam from its idealized path.